My name is Zdenek Prudil and I am a Ph.D. Student in Astronomy at the Astronomisches Rechen-Institut in Heidelberg. I am working in prof. Eva Grebel's group. My research is focused on the Galactic archeology using RR Lyrae stars to trace the spatial and kinematical structure of the Milky Way and its neighborhood. I am also interested in studies of stellar pulsations from photometric and spectroscopic data.

Below you can see my current research projects:

Pic 01

The Oosterhoff dichotomy in the Galactic bulge - kinematical distribution

Following up on our previous project we studied the kinematical distribution of RR Lyrae stars in the Galactic bulge. We used proper motions from the Gaia space telescope and publicly available radial velocities to obtain a 6D solution for 429 variables in two Oosterhoff groups. We found that RR Lyrae stars in both groups does not differ from the kinematical point of view, and the kinematics of our sample RR Lyrae stars is consistent with the random motion expected for a classical bulge component.

Pic 01

Candidates for binary systems with RR~Lyrae stars

One of the long-term problems that hamper the use of RR Lyrae stars is the uncertainity in mass due to lack of known RR Lyrae stars in binary systems. So far only over one hundred RR Lyrae variables are marked as possible binary candidates. In this project, we provide an additional 20 binary candidates with an RR Lyrae component based on the light-travel time effect (LiTE) hypothesis.

Pic 01

The Oosterhoff dichotomy in the Galactic bulge - spatial distribution

The Milky Way globular clusters can be divided into two (three) groups based on the pulsation properties of their RR Lyrae stars. In this project, we investigated the RR Lyrae variables in the Galactic bulge. We found that the central region of our Galaxy contains two Oosterhoff populations of RR Lyrae stars, similar to the Milky Way globular clusters.

Pic 02

Variable stars in the SMCNOD

One of the discoveries of the Dark energy survey was a small overdensity north from the Small Magellanic cloud. Using the available photometry for variable stars we studied this overdensity and linked its origin the Small Magellanic cloud.

Pic 02

Photometrics study of the Blazhko effect

The Blazhko effect among RR Lyrae stars has been puzzling astrophysicist for over a century. In this paper, we searched for differences between RR Lyrae variables with and without the Blazhko modulation. We found that the Blazhko effect comes in all shapes and flavors and that stars affected by this enigma differs from non-Blazhko stars. Both groups can be roughly separated on the basis of their pulsation properties.

Pic 01

Peculiar double mode RR Lyrae stars

In this project we found 42 RR Lyrae stars that exhibit additional pulsation mode. We performed period analysis on available photometry and found additional peaks in the frequency spectrum, that are related to additional pulsation mode. The additional mode cannot be explained by the current pulsation models and its origin is unclear.